They were using some new blast resistant concrete (not sure on the details, maybe not so new). The expectation was that it would ablate somewhat this time and t

They were using some new blast resistant concrete (not sure on the details, maybe not so new). The expectation was that it would ablate somewhat this time and they could resurface it and install deluge system for next time. Turns out instead of ablating a little is shattered and left the area in chunks exposing the sand underneath to be blown away as well. I can see why the idea of no flame trench is alluring. Imagine the capability to land a rocket on essentially a parking lot, refueling and taking off again. You could land and take off on the moon or Mars like that too. But that's outdated by now. There's an orbital launch mount and once you need that you might as well have a trench too.